True or False: Is Mistletoe the "Kiss of Death?"

There is a myth about American Mistletoe, the green-berried parasitic plant often hung in doorways during the holiday season to elicit kisses from those standing beneath it. Reputed to be the "kiss of death," it is said to be so poisonous that humans can be killed if they ingest the leaves or berries. This myth has been endlessly repeated throughout the years, reappearing every December in countless holiday safety reports on television and in print.

Is it true? Is American Mistletoe (Phoradendron species), a holiday killer? Two physicians and researchers from Pittsburgh decided to find out. Dr. Edward P. Krenzelok (Children's Hospital of Pittsburgh) and Dr. Terry Jacobson (Carnegie Mellon University) examined data from the American Association of Poison Control Centers and found 1,754 reports of mistletoe exposure over a seven-year span. Curiously, not only had no one died of mistletoe poisoning, in the overwhelming majority of the cases (approximately 90 percent), the patient experienced no effects at all. Those patients who did have effects suffered only minor discomfort. Treatment at a poison control center or at home made no discernible difference in patients' recovery or outcome.

Most mistletoe ingestion is reported in children, often those under two, who finding a couple of berries or leaves that have dropped to the floor will put them in their mouths. Drs. Krenzelok and Jacobson found that such exposure was not dangerous, and that the children could be observed and treated for poisoning symptoms, such as nausea or diarrhea, at home. They suggest that parents call their local poison control center and follow the advice given. The study did not indicate whether ingestion of large quantities of mistletoe might be more toxic, nor did it address the degree of exposure that might be toxic in pets (who might be inclined to eat a larger quantity than a child).

Causing at most only minor discomfort, American Mistletoe does not seem to have earned its reputation as the "kiss of death." Its European cousin, Viscum album, sometimes used in herbal remedies, is more toxic, but is not sold commercially in North America and is thus rarely encountered.